The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Galvanic isolators may refer to devices using insulation to electrically separate electrical circuits in different power domains such that current does not flow from one electrical circuit in one power domain to another electrical circuit in another power domain. A galvanic isolator may transfer electrical power or electrical signals from one power domain to the other power domain across an insulation barrier. For example only, a transformer provides (inductive) galvanic isolation between a primary winding and a secondary winding. Transformers can be used for transferring power or signals between circuits of different power domains. Other example types of galvanic signal isolation include capacitive galvanic isolation, optical galvanic isolation, etc. Even using galvanic isolators, negligible alternating current (AC) currents may still flow between power domains due to parasitic capacitance.
Large voltages can exist between the power domains. This voltage appears directly across thin electrical insulation of galvanic isolation devices. The insulation, however, can deteriorate, such as due to aging and/or large voltage transients. Failure of the insulation allows unwanted current to flow between power domains.